Reference no: EM132927695
EMMOM2A Mechanics of Machines - Vaal University of Technology
Experiment - Flat Belts
AIM
1. To determine the relationship between the high-tension side T1, and the low-tension side T2, of a Flat belt and
2. To determine the frictional coefficient μ of a Flat belt.
A. calculate and complete table 1.
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Contact angle
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Load
T1 = mass x 9,81
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Load
W = string in N
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T2 = T1 - W
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T1/T2
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m
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30°
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2 x 9.81
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2.021
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4x 9.81
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3.002
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6 x 9.81
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5.454
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8 x 9.81
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6.435
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10 x 9.81
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7.416
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60°
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2 x 9.81
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3.492
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4x 9.81
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6.435
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6 x 9.81
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9.869
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8 x 9.81
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12.321
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10 x 9.81
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15.264
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90°
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2 x 9.81
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4.473
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4x 9.81
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8.397
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B. Draw a graph with T1 (x-axis) against T2 (y-axis) for all the contact angles on the same axis( graph chart).
C. Determine the slopes for the graph (T1/T2) and the frictional coefficient (μ) for every contact angle.
D. Fill in the following table:
E. Determine the average frictional coefficient
F. How much torque can the pulley-belt system transmit for 30°, 60°, 90°,120° contact angle? If the pulley has a diameter of 80mm.
G. what have you learned from this experiment? Give your conclusion
Experiment - Cone Friction
AIM
1. Study the effect of the conical angle of a pivot bearing.
2. To determine the frictional coefficient between two bearing surfaces if wear is uniform.
3. To determine the relationship between the frictional torque T and the angle α.
4. To determine the relationship between the frictional torque, T, and the axial load W.
1. The minimum radius R1 and the maximum radius R2 of the bearing surface and the effective diameter of the turntable were Determined.
2. The apparatus was assembled and start with 600 conical bearings.
3. the load hanger cords were winded up around the periphery of the rotating table.
4. 2 kg mass was loaded to axial load on the top plate, to determine the torque needed to rotate the top plate at a steady, constant speed. The effective diameter of the top plate is 230 mm.
5. Another 2 kg mass was added to the axial load on the top plate. To Determine the torque needed to rotate the top plate at the same steady speed as before.
6. As Continuation, added additional 2 kg mass pieces to a maximum of x kg, and for every weight determine the torque needed to rotate the top-plate at the same constant speed.
7. To ensure that the same constant speed is obtained for every system of axial loads, the time for one revolution of the turntable was noted.
8. Repeat the experiment for the 90°.
i. Tabulate the results for each of the 2 bearings as follow:
ii. Determine the average radius of each bearing:
iii. Tabulate the results as follow:
iv. From table 2-2 Convert load torsion/force load into Torque (Nm), and tabulate your results in table 2-3.
v. Draw a graph of frictional torque T (y-axis) against load W (x-axis) for each set of results.
vi. Calculate μ for each set of results. Use the following formulas and read T/W from your graph.
Conclusion
• Compare the theoretical values and practical values for torque on 600, 900
Note: Need only experiment 2
Attachment:- Mechanics Of Machines.rar